The average 5-year survival for colorectal cancer (CRC) is less than 10% if metastasis occurs, but can reach 90% if detected early. A new non-invasive test has been developed that measures methylation of the SDC2 gene in tissues and blood sera.
This test detected 87% of all stages of colorectal cancer cases (sensitivity) without significant difference between early and advanced stages, while correctly identifying 95% of disease-free patients (specificity). The results are published in the July issue of The Journal of Molecular Diagnostics.
According to the US Centers for Disease Control and Prevention, CRC is the second leading cancer killer in the US affecting both men and women. In 2009, close to 137,000 people in the US were diagnosed with CRC, with close to a 40% mortality rate.
There are other screening choices for CRC, including fecal occult blood testing (FOBT), fecal immunochemical testing, and colonoscopy. Colonoscopy is the gold standard of CRC screening, but patient resistance – mostly due to the unpleasant preparation – has curbed widespread adoption. FOBT is non-invasive but has limited sensitivity, particularly for early disease. A sensitive and specific non-invasive test using blood or stool could to be a more preferable option with the potential of saving many lives.
In their search for a biomarker that could be used for the early detection of CRC, investigators from Genomictree, Inc. and Yonsei University College of Medicine in Seoul, South Korea, performed DNA microarray analysis coupled with enriched methylated DNA using tissues from primary tumors and non-tumor tissues from 12 CRC patients. After step-wise filtering, they found a set of genes that were highly methylated across all of the CRC tumors. Ultimately they identified one gene, SDC2, which encodes the membrane syndecan-2 protein, a protein that is known to participate in cell proliferation, cell migration, and is expressed in colon mesenchymal cells. The methylation level of target region of SDC2 assessed in tumor tissue was found to be significantly higher than that from paired adjacent non-tumor tissue.
The next step was to clinically validate the biomarker by analyzing SDC2 methylation levels in primary tumors and paired-adjacent non-tumor tissue samples from 133 CRC patients. Investigators found that in the transcriptional regulatory region of the SDC2 gene, tumor samples showed significantly higher levels of methylation than the control samples. SDC2 methylation positivity ranged from 92.9% to 100% when samples were stratified according to stages of cancer.
Further, investigators found that the SDC2 biomarker could be measured in serum samples from CRC patients and healthy individuals. "The SDC2 methylation test was able to detect 92% for detection of stage I cancer patients indicating that SDC2 is suitable for early detection of CRC where therapeutic interventions have the greatest likelihood of curing the patient from the disease," says first author TaeJeong Oh, PhD.
The authors suggest that the SDC2 methylation test they describe could possibly be used as an alternative to or in conjunction with colonoscopy. It could also be used to monitor cancer progression and treatment. Dr. Sungwhan An, corresponding author and CEO of Genomictree, Inc., commented: "We are very excited with this result using a small amount of serum DNA from less than 1ml of blood. I believe a greater volume of blood will further improve the clinical performance of this test. We are currently preparing another set of clinical validation studies evaluating SDC2 methylation in serum DNA from patients with early adenoma." In future research the authors will explore whether this biomarker is specific to CRC or universal among other cancers.
David Sampson | EurekAlert!
Fingerprint' technique spots frog populations at risk from pollution
27.03.2017 | Lancaster University
Parallel computation provides deeper insight into brain function
27.03.2017 | Okinawa Institute of Science and Technology (OIST) Graduate University
Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.
The results will be published on March 22 in the journal „Astronomy & Astrophysics“.
Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...
Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.
Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...
In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...
20.03.2017 | Event News
14.03.2017 | Event News
07.03.2017 | Event News
27.03.2017 | Earth Sciences
27.03.2017 | Life Sciences
27.03.2017 | Life Sciences